import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';

export function middleware(request: NextRequest) {
  const url = request.nextUrl;
  
  // Check if there is a referral parameter ?ref=
  const ref = url.searchParams.get('ref');
  
  if (ref) {
    const response = NextResponse.redirect(url.pathname);
    // Set cookie for 30 days
    response.cookies.set('vw_referral_agent', ref, {
      maxAge: 30 * 24 * 60 * 60,
      path: '/',
      httpOnly: true,
      secure: process.env.NODE_ENV === 'production',
      sameSite: 'lax',
    });
    return response;
  }
  
  return NextResponse.next();
}

export const config = {
  matcher: [
    /*
     * Match all request paths except for the ones starting with:
     * - api (API routes)
     * - _next/static (static files)
     * - _next/image (image optimization files)
     * - favicon.ico (favicon file)
     */
    '/((?!api|_next/static|_next/image|favicon.ico).*)',
  ],
};